Filtering and Assessing the Sample Size of Tracking Data R package SDLfilter version 2.3.3 CRAN Task View: Tracking (https://CRAN.R-project.org/view=Tracking) Functions to filter GPS/Argos locations, as well as assessing the sample size for the analysis of animal distributions. The filters remove temporal and spatial duplicates, fixes located at a given height from estimated high tide line, and locations with high error as described in Shimada et al. (2012) <doi:10.3354/meps09747> and Shimada et al. (2016) <doi:10.1007/s00227-015-2771-0>. Sample size for the analysis of animal distributions can be assessed by the conventional area-based approach or the alternative probability-based approach as described in Shimada et al. (2021) <doi:10.1111/2041-210X.13506>. Software Depends: R (>= 3.5.0), ggplot2 Imports: geosphere, data.table, gridExtra, ggmap, maps, pracma, lubridate, dplyr, emmeans, utils, sf, stars, ggspatial Takahiro Shimada <taka.shimada@gmail.com> Comprehensive R Archive Network (CRAN) Takahiro Shimada GPL-2 file LICENSE (https://CRAN.R-project.org/package=SDLfilter/LICENSE) 2023-11-10 application/tgz https://CRAN.R-project.org/package=SDLfilter doi:10.32614/CRAN.package.SDLfilter